"He lost me here. How did he get these dates?"
Hal Lindsey's earlier books are all based upon the dispensationalist assumption that the Tribulation and Armageddon would occur within a biblical generation (40 years, per Lindsey) of the reestablishment of Israel in 1948. While I'm not aware of Lindsey acually putting it to print, if you do the math you arrive at the conclusion that the Second Coming must occur by 1988. Lots of other people did do that math, and if you don't believe me, check out the massive wave of "end times" literature that was published in the 80s, and the dearth of it after 1989.
So however Lindsey's getting his current dates, I'm sure it's the same method that led him to believe that the world was headed for Argageddon back in the 80s....namely, via newspaper exegesis and dispensensationalism....
"So however Lindsey's getting his current dates, I'm sure it's the same method that led him to believe that the world was headed for Argageddon back in the 80s....namely, via newspaper exegesis and dispensensationalism...."
You're right. Edgar C. Whisenant released "88 Reasons Why the Rapture Is in 1988." Some have since revised the theory to say that the 40 years was meant to be after the capture of Jerusalem, placing the Rapture in 2007. This isn't widely stated, however, probably for fear that they'll be wrong again.
I have it on good authority that the exact date for His return is hidden in P-M's tag line.